Removable inserts for pipe passages in concrete



Jan. 24, 1961 v w. J. STOLZ 2,968,855 REMOVABLE INSERTS FOR PIPEPASSAGES. IN CONCRETE Filed March 24, 1958 FIG.

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FIG. 5 I FIG. 6 INVENTOR WILLIAM J. STOLZ ATTORNEYS United States Patent6) F REMOVABLE INSERTS FOR PIPE PASSAGES IN CONCRETE William J. Stolz,333 West Ave., Elyria, Ohio Filed Mar. 24, 1958, Ser. No. 723,306

2 Claims. (Cl. 25'-128) This invention relates to a removable pipesleeve.

It has been proposed to form passages in floors or walls in reinforcedconcrete buildings through which pipes of various types are passed andthese passages are formed by constructing wooden boxes in connectionwith steel and conductor pipe filled with sand which must be carefullyattended when the concrete is poured and during the setting of theconcrete. All of these elements, however, must be destroyed before theycan be removed which causes added expense for labor and material.

It is an object of the present invention to provide a removable form forconstructing passages in concrete used in buildings so that pipes ofvarious kinds employed for plumbing, heating and other equipment may beinserted through the passages, the removable form including a rubber orelastic sleeve which is expanded internally by a coil spring whenpressure is exerted upon the opposite ends of the spring, the spring,sleeve and associated elements being removable from the passage afterthe poured concrete has set for use many times thereafter.

Another object of the invention is the provision of a device for formingopenings in the walls of buildings when concrete is employed in which anexpansible sleeve is secured in position at the desired point withinternal means for expanding the sleeve so that after the concrete hasbeen poured and set around tne sleeve the same may be retracted andwithdrawn to leave a passage of suitable diameter for the insertion ofvarious kinds of pipes.

This invention relates to US. Patent No. 2,234,784 and is acontinuation-in-part of application Serial Number 591,400, filed June14, 1956, which application is specifically abandoned in favor of thismore full teaching of the invention.

It is a principal object of this improved invention, over the prior artand application, to provide a spring formation which will eliminate theneed for the plates required for end support of the device.

Another specific object of utmost importance is the provision of atapered external sleeve formation, in order to produce a tapered openingthrough a floor slab and thereby hold a flood preventative sleeve linerin the finished passageway through the concrete, and permit masticsealing of the sleeve, without the use of external support devices.

Other objects and a fuller understanding of the invention may be had byreferring to the following description and claims taken in conjunctionwith the accompanying drawing, in which:

Figure l is a vertical section of a device constructed in accordancewith the principles of this invention;

Figure 2 is a section through a tapered floor opening with a sleeveliner positioned therein; the drawing does not illustrate'sealing masticin the resultant annular space in the interest of clarity ofillustration;

Figure 3 is a section through a poured slab, with the liner devicepartially broken away, the section being i1- 2,968,855 Patented Jam. 24,1961 lustrated vertically but being applied more frequently tohorizontal wall sections;

Figure 4 is an end view of the improved spring liner;

Figure 5 is a vertical section of a device constructed in accordancewith this invention, as applied to a mesh 01- screen form; and,

Figure 6 is an illustration of the use of the device on a slopedsurface, and tripod means to adapt the device to such sloped surface.

When installing standpipes, capped drains or the like in concretefloors, it is good building practice and, in many cases required bybuilding codes or to fulfill Fire Underwriters Specifications, that suchconduits extend a specified distance above the finish floor line and besealed in the floor. This, in the event that water should accumulate onthe floor, it would be prevented from running down around the pipe tothe floor below.

An insert for forming passages in floors to allow installation of pipesor tubes in accordance with such requirements is illustrated in Figure1, wherein 10 designates the insert generally. In Figure 1 insert 10 isshown in- Y stalled on a wooden form 12 which supports the pouredconcrete mixture 14. conventionally, mixture 14 is a coarse-aggregatemix which forms the floor slab. Reference numeral 16 designates thepassage formed by the insert.

Insert 10 comprising a sleeve 18 of a deformable, resilient materialsuch as rubber. The sleeve is usually of circular cross-section, asshown, although this is a matter of selection depending on thecross-section of the passage to be formed. Thus the sleeve may have, forexample, an oval, square-rectangular, or other cross-section. The normalaxial dimension of sleeve 18 exceeds, at least slightly, that of passage16, so that its upper end projects above the top surface of the concrete14, even when the sleeve is longitudinally compressed in use, ashereinafter explained. The wall thickness of sleeve 18 should besubstantial, depending on the compliance of the material of which it ismade, so that it will retain its shape under normal handling andstresses.

In the particular embodiment being described, the lower end of sleeve 18has its outer wall formed with an inwardly tapering portion 20 whichextends along a substantial minor part of the sleeve-length. Inpractice, the tapered portion 20 would extend at least an inch or twoand would be tapered at an angle of perhaps 15 degrees or more to thesleeve axis.

Coaxially disposed within sleeve 18 is a simple coil spring 22 having anunstressed or relaxed length roughly in. longer than that of the sleeve.The outer diameter of the spring is such that the convolutions engage ornearly engage inner wall 24 of sleeve 18.

Previously, an end plate has been used to support the end of the sleeve18 and hold the end of the coil spring. According to this invention, theend convolution of the spring has been formed into a final convolutionlying substantially in a flat plane with the extreme end of the wire ofthe spring jutting inwardly to an eye loop 27 on one end of the springand an eye loop 28 on the other end of the spring. Each end convolutiondefines an outer part 80, A at opposite ends of the spring. The eyeloops 27 and 28 encompass the central longitudinal axis of the springspiral. Hence, the improved spring of this invention does not requirethe use of extraneous end cap members or other accessory means forestablishing a fixed longitudinal axis pin.

The sleeve 18 has a first end 11 defined by an annular end Wall surface50 lying in a plane which is a continuation of the plane of the finalconvolution of the spring and its eye loop 28. Likewise, the sleevehas asecond end 11A defined by an annular end wall surface 50A which likewisedefines a plane which corresponds to the plane of the end convolutionand its eye loop 27. Thus, the sleeve end walls and the spring ends lieand abut a common fiat plane surface in order to provide a common seatfor the structure without the need for other end devices to level oraffix the structure.

A cap plate 34 is provided to sit upon the end of the sleeve 18 in orderto employ the screw 38 to apply .pressure longitudinally upon the sleevemember.

Extending coaxially through alinged apertures 32, 36 and sleeve 18 is ascrew member 38, one end of which carries a screw head 40 which bears onplate 34 and is adapted to be engaged by a suitable-preferably conventional-tool for turning it. The screw member is substantially longerthan sleeve 18, and, at its end opposite head 40, is provided with screwthreads 42 adapting it to be secured by a toggle head 39.

An improved toggle device 39 is employed as an anchor for the screw 38.This toggle device is a one-piece device without the provision of anyspring or intermediate pivot. A threaded collar 42 fits the screw 38 andis provided with laterally extending pins 40, which are not shownbecause of the cross-section in Figure l, but are shown in the Figure 5.The collar is concealed under the toggle 39 and is therefore notrevealed in the drawing, but is of usual nut-like structure. By the useof such device, constructed off center as illustrated, the toggle may beallowed to tilt by gravity for the purpose of inserting the togglethrough a convenient form opening and to be just as readily removed backthrough the opening, while being retained on the end of the screw 38.Thus, there is no loss of such toggle device as would be necessary withthe use of a spring actuated toggle,

The insert described above operates in the following manner: thecenter-line of the passages to be formed is determined and marked on thewooden form 12. Preferably, this location is marked with a center-punchand then drilled. Thereafter the insert is assembled by first slippingscrew member 38 through aperture 36 of plate 34, slipping the spring 22over the shank of the screw member, and then into the sleeve 18. Fromthe structure described it will be appreciated that the improved new endconfigurations of spring 22 serve to automatically establish aconcentric relation between the screw member and spring and, in turn,between the screw member-spring assembly and the sleeve. The screwmember is tightened up until substantial pressure is exerted on the endsof sleeve 18, thus compressing both spring 22, and sleeve 18.Compression of spring 22 is reflected in a slight increase in itslateral dimension which takes up any peripheral clearance which mayexist between the spring convolut ions and inner sleeve Wall 24 and thenexerts a radially outward pressure tending to increase the lateraldimension of the sleeve. In addition, due to the Well-known Poissoneffect, the axial compressive stress exerted on sleeve 18 by screwmember 38 produces a lateral strain which, in a hollow body like sleeve18, tends to thicken the walls,

i."e., increase the outer dimension and diminish the inner dimension.The latter effect, however, is resisted by the "radially outwardlydirected force exerted by the convolutions of spring 22 and the netresult is a general expansion or increase in the outer lateral dimensionof sleeve 18, the expansion being substantially uniform along the entirelength of the sleeve so that there is no spurious distortion of thesleeve.

At this stage the insert is in place and ready for the pouring of theconcrete mixture 14. While it is rarely necessary, the outer surfaces ofthe sleeve may be lubricated to preclude adherence of the concrete.After the concrete has been poured and has set sufficiently, the insertis removed by simply removing screw member 38. This allows plate 34 tobe removed whereafter spring 22 is slipped out of sleeve 18. The sleeve,which returns to its original dimensions when the screw member islooserred, can usually be gripped and pulled out without difiicultyalthough its deformable character may be re sorted to if necessary tosimplify removal. Obviously, the amount of clearance between the relaxedsleeve and passage 16 is, within limits, a function of the amount ofpressure exerted on the sleeve during setting of the concrete.Therefore, the degree of tightening of screw member 38, which isobviously within the control of the operator, may be selected to achievethe desired clearance, a few thousandths of an inch usually beingsufficient.

Removal of insert 10 leaves passage 16 having an inward, conical taper44 at its lower end. Referring to Figure 2, the pipe 01" tube 46, ofappropriate length and diameter, is slipped into passage 16, its lowerend seating a taper 44. Thereafter, a suitable water-proof groat istamped into the clearance "around the tube at the upper surface of slab14, thus forming a water seal at 48. Thereafter, the finish floor 50 ispoured over slab 14 to complete the installation. The great is not shownin Figure 2 because the small space would confuse the illustrativedrawings. 7

A modified form of the invention is shown in Figure 3 and designatedgenerally by reference numeral 119. In describing this embodiment, partsidentical or wholly analogous to those in the first described embodimentwill be identified with the same numerals of reference increased by afactor of 100.

Insert is particularly adapted for use in forming passages in concretewalls, constructed by pouring the concrete mixture between substantiallyparallel wooden forms, such as designated at 112 and 112a Figure 3. Thelocus of the passage to be formed is defined by respective coaxiallyaligned holes 111 and 111;: in terms 112 and 112a. Insert 110 comprises,a sleeve 118, and a screw member 138 all of which are generallyfurictiohally equivalent to corresponding parts in Figure 1;

However, two coil springs 122 "and 122a are used. In

dividually, springs 122 and 122a arestructurally identical to spring 22,Figure 1. More springs are used for thicker walls.

Springs 122 and 122a are placed end-to-end, within sleeve 118 in coaxialalignment with each other and with the sleeve. The respective endconfigurations of springs 122 and 122a abut each other and thecorresponding ey'e loops 27 are in registration, although hidden fromview in the Figure 3. Among the several advantages of two springs inthis particular construction are: (1) additional guiding and supportingeffects, which may be necessary in a horizontal installation andparticularly with a long passage, are provided; (2) such effects areprovided "a lower cost, as compared to a single long spring speciallymanufactured for such limited use; (3) the springs may be usedindividually in a shorter insert. Many short sleeves -18 may also beemployed.

Continuing with the description, the axial dimension of sleeve 118 andthe contined unstressed length of coil springs 122 and 122a shouldexceed slightly the aggregate axial dimensions of passage 116 and thetwo holes 111, 111 The lateral dimensions of the springs 122', 122aconform to the detailed description of the corresponding parts inFigure 1. However, the plates 134 and 134a are of such peripheraldimension and configuration that they extend beyond the margin of holes111, 111a for a purpose which will be apparent presently.

Preferably, screw members 138 have screw threads 1'42, 142a at both endsfor the engagement of suitable nuts143, 143a which bear on plates 134,"134.1. The manner of installation and operation of insert 110 isbelieved obvious from the structure described and the detaileddescription given in conjunction with Figure 1.

However, it should be noted that by virtue of the plates 134, 134aextending beyondholes 111, 111a, screw member 138 becomes effective as atie-rod for the forms, precluding separation thereof under the weight ofthe concrete mixture 114.

Figure 5 is an illustration of the invention employed on a screenformrather than on a wooden support. ,1?

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is supplied for the purpose of illustrating the versatility of theinvention. Figure 5 illustrates a feature of the invention which enablesadjustment of the angle between the axis of the passage and thesupporting form. It may be employed as a leveling device, for example,to achieve a vertical passage in a slab which is not preciselyhorizontal. Conversely, it may be used to create a passage which doesnot extend perpendicular to the form.

The adjustment feature is illustrated as applied to an insert as inFigure l, with the addition of an adaptor plate 340. Plate 340 containsone or more tapped holes, each of which threadedly receives anadjustment screw such as cap screw 41.

In Figure 6, support form 120 is at an appreciable angle to thehorizontal. Insert 10 is installed in the same manner as previouslydescribed, but by selective adjustment of screws 41 and plate 340, maybe leveled so that the axis of the insert is substantially vertical.Preferably two screws 41 are employed to provide a tripod support. InFigure 6 the second screw 41 is hidden from view.

Although the invention has been described in its preferred form with acertain degree of particularity, it is understood that the presentdisclosure of the preferred form has been made only by way of exampleand that numerous changes in the details of construction and thecombination and arrangement of parts may be resorted to withoutdeparting from the spirit and the scope of the invention as hereinafterclaimed.

What is claimed is:

1. A device for forming passages in concrete structure work comprisingan elastic sleeve around which concrete may be poured and which therebyforms a passage in the concrete, said sleeve having a first end definedby an annular end wall surface lying in a first plane, said sleevehaving a second end defined by an annular end wall surface lying in asecond plane, said first and second planes being substantially parallel,a coil spring retaining said sleeve in extended position and fullyexpanded condition during the pouring and setting of the concrete, saidspring having a central longitudinal axis with a spiral configurationtherearound defining a cylinder surface corresponding to the interiorsurface of the sleeve, said spring having first and second endconfigurations, each end configuration including an outer part disposedin said cylinder surface defined by the spiral configuration, the firstend configuration including a first arm part extending generallyradially inwardly from the first end outer part and terminating in anend eye loop part circumscribing said axis, the second end configurationincluding a second arm par-t extending generally radially inwardly fromthe second end outer part and terminating in an end eye loop partcircumscribing said axis, said first and second end configurationshaving first and second end wall surfaces respectively, said first endwall surface of said spring first end configuration defining one surfaceof said first end configuration part and said second end wall surface ofsaid spring second end configuration defining one surface of said secondend configuration part such that each of said end wall surfaces of saidspring end configuration circumscribes said longitudinal axis, saidfirst end wall surface of said spring first end configuration beingdisposed in its entirety in the first sleeve end plane, said second endwall surface of said spring second end configuration being disposed inits entirety in the second sleeve end plane, said end configurationsserving as an internal expansion end support for the sleeve and as abase for the composite device and means projecting through said end eyeloops for expanding the spring against the walls of the sleeve forexpanding the sleeve before concrete is poured.

2. The device of claim 1 wherein said first and second sleeve end wallsurfaces are at top and bottom ends and wherein the sleeve outer surfacetapers outwardly from the bottom end toward the top end and terminatesat a location between the longitudinal midpoint of the sleeve and thebottom end, the internal diameter of the sleeve is relatively constantthroughout its length.

References Cited in the file of this patent UNITED STATES PATENTS427,914 Schilliger May 13, 1890 1,391,988 Zents Sept. 27, 1921 1,396,280Paine Nov. 8, 1921 2,138,015 Barnhart Nov. 29, 1938 2,234,784 Stolz Mar.11, 1941 2,311,358 Baily Feb. 16, 1943 2,527,874 Bradley Oct. 31, 19502,720,017 Youtz Oct. 11, 1955 2,721,369 Burke Oct. 25, 1955

